Replying to this 4 month old post because I can't remember where the recent original DOOM discussion was and the forum's search function is STILL fucked.
DOOM & DOOM II on Steam recently got an update and I finally got around to playing it. I have to say, replaying original DOOM has been a fucking blast. This old style of shooter game still holds up, and this particular version of the game has been fully updated for modern hardware/software. It even supports my native 5120x1440x120. Note: context for the below is Ultra-Violence difficulty. I've never played any of these original DOOM games on any difficulty other than UV, except for occasionally fucking around with NM, but I can't abide infinitely respawning monsters, I'm not a speed runner type personality. I must scour the level of all demon scum.
DOOM's 4 episodes have an almost-perfect difficulty curve. Ep 1 is very basic, gives you plenty of resources, doesn't even use some of the tougher enemies like Cacodemons, only 2 Barons (as Episode bosses), etc. Great intro to the game.
Episode 2 introduces Cacodemons and my personal arch-nemesis the Lost Soul (omg those fuckers), and throws in higher numbers of tougher, meatier monsters all while supplying you with less ammo making conservation and efficiency start to matter. Ends with a showdown with the biggest fucker you've seen yet, the Cyberdemon, which is just so great. I can't tell you how great it felt to underestimate him since this was my 40th time playing DOOM (albeit 10+ years since last), only to eventually eat a rocket straight to the chin knocking me down to 50% health and no armor. Humbled, I laughed it off and finished him.
Episode 3 opens by throwing two cacodemons at you with only your pistol available (unless you run forward to grab a shotgun), and only escalates from there. Again, the monsters are more dense, more higher level monsters, ammo is even more scarce, and unless you're great at finding all the secrets some weapons take forever to make their way into your arsenal. I don't actually recall if the BFG is handed to you in a non-secret area because I scour every level for every secret I can find, but this one intros the BFG. So satisfying gibbing a room full of 15-20 soldiers and imps with one shot. Fantastic episode and nice Hell themes even back in the 1990's textures. Spider Mastermind is a decent end boss, although if you have enough energy cell ammo the BFG makes entirely-too-quick work of him. My playthrough yesterday reduced him to rubble without him being able to spin up his mega-chaingun. Ah well.
Episode 4 (released shortly after DOOM II came out, I believe) is another thing entirely. Hoo boy I had forgotten how ass-rapey this one is. I'm paused at the end of Mission 2 to type this out. I died 5-6 times before finding my way through Mission 1 (context: died 1 time total in Eps 1-3), and died another 2ish times (with a couple reloads based on poor performance knowing I'd not live through it) on this mission. They are total dicks with this one: throwing multiple Barons at you MULTIPLE times in cramped-ass quarters, tricky shit like reserves of monsters sitting behind fake walls ready to wake up and be teleported into your active area as you make progress... the opening of Mission 2 is hysterical, you're immediately faced with a half-dozen imps and another half-dozen cacodemons, coming from Mission 1 where you'd be lucky to come out with more than a handful of bullets, maybe 30 shells, and several rockets.
The way you can play enemies off each other is fun, and I don't recall that really being a thing with the newer DOOMs, or many games in general. It's often the key to ammo efficiency, allowing a room full of *insert enemy type* and *insert second enemy type* piss each other off with friendly fire. I actually played with the old level editor CAD systems quite a bit and made my own campaign as a young nerd, and one of the levels I had made involved giving you no ammo and requiring you to utilize enemy friendly fire to clear a large room of shit. I spent a lot of time fucking with that level editor, fun times.
Really looking forward to wrapping up Ep4 and moving on to DOOM II. My fondest memories are of that campaign. There are so many moments throughout these where as soon as I load into the level I remember exactly what is waiting for me, and dread it. They really managed theme and balance here to make every enemy an interesting threat. Each enemy type, you encounter it and you're like "oh fuck, not these fuckers." Obvious exception being pistol soldiers. And that Cacodemon alert sound... the thing of nightmares. Also looking forward to the super shotgun, Pinkies and Spectres are annoying without it. Then there's all of the other "master level" campaigns they bundled into this one, a couple of which I have never played. I bought and played Final DOOM (Evilution and Plutonia Experiment), but I've never heard of No Rest for the Living, Sigil, or Legacy of Rust, which apparently has new enemies and weapons, and all of which are semi-official or official. Tons of content here for $10.
Apparently, they've done a great job of getting co-op up to modern speed as well. Some of my best childhood memories are playing DOOM and DOOM II campaign co-op with friends and family. If anyone ever feels like it, the game is $10 (or less), hit me up in DM's or on FoH Discord and I'll play some DOOM with you sometime.
One of these days I will make a (hopefully worthy) successor to DOOM. This old-style frenetic "just kill the enemies" type of gameplay still has a place in gaming. No need for extra bullshit mechanics. Just pick up weapons and slaughter enemies. Lots and lots of enemies.